Up or Down Vote (thumbs up or thumbs down)

An “up or down vote” is a straight “yea or nay” vote on an amendment or a bill. An “up or down vote” can also be called a “clean vote,” although that usually refers to a direct vote on an issue, without amendments.
 
“Voted up or down” has been cited in print since at least 1860 and “up or down vote” since at least 1932. “‘Thumbs up’ or ‘thumbs down’” has been cited in print since at least 1870.
 
 
Wikipedia: Up or down vote
An up or down vote refers to a direct vote in the U.S. House of Representatives or the U.S. Senate on an amendment or bill; it is sometimes referred to as a “clean vote”. Members vote yea or nay on the matter rather than voting on a related procedural maneuver. Depending upon the rules of order for that particular type of amendment or bill, the vote required for passage might be a 2/3 majority, a 3/5 majority, or a simple majority.
 
C-SPAN Congressional Glossary
An UP OR DOWN VOTE refers to a direct vote on the substance of an amendment or bill, sometimes referred to as a “clean vote.” Members simply vote yea or nay on it.
 
Many votes dispose of a matter indirectly through another motion, e.g. to table, to recommit, to amend in the second degree.
 
Members often seek “up or down” votes because they are less cumbersome and therefore easier to explain.
             
(Oxford English Dictionary)
thumb, n.
(a) In expressions referring to the use of the thumb by the spectators in the ancient amphitheatre, to indicate approbation or the opposite: see quot. 1880;  (b) in mod. use (with significance the reverse of that in the ancient amphitheatre): thumbs down, thumbs up, gestures made with the fingers closed and the thumb pointing vertically downwards (indicating disapproval or rejection) or upwards (as a sign of approval, acceptance, encouragement, etc.); also attrib. and fig.
1601 P. Holland tr. Pliny Hist. World II. xxviii. ii. 297   To bend or bow downe the thumbes when wee give assent unto a thing, or doe favour any person.
1693 Dryden tr. Juvenal Satires iii. 35   Where‥With Thumbs bent back, they popularly kill.
1880 C. T. Lewis & C. Short Lat. Dict. at Pollex,  To close down the thumb (premere) was a sign of approbation; to extend it (vertere, convertere; pollex infestus) a sign of disapprobation.
1887 R. Garnett Life Carlyle iv,  They had unanimously turned their thumbs up. ‘Sartor’, the publisher acquainted him, ‘excites universal disapprobation’.
1906 R. Kipling Puck of Pook’s Hill 180   We’re finished men—thumbs down against both of us.
1907 R. Y. Tyrrell in Academy 9 Mar. 234/1   ‘Thumbs down’ means ‘spare him‥’: the signal for death was ‘thumbs up’.
1917 A. G. Empey Over Top 311   Thumbs up, Tommy’s expression which means ‘everything is fine with me’.
     
16 May 1860, Sandusky (OH) Register, “Judge Brinkerhoff,” pg. 2, col. 3:
A man who “don’t care whether slavery is voted up or down,” won’t suit them.
 
Google Books
August 1865, Indiana School Journal, pg. 276:
We have time and again said that the youth of this Government must understand the principles of their Government. The responsible and potential act of voting up or down certain great principles of this Government, without the remotest understanding of these principles, or even remotest attempt to understand them, is not only the play of Hamlet with Hamlet left out, but it is the play of an ignorant sovereign (one of the people) with the immortal interests of the American Republic.
   
16 May 1868, Salt Lake Daily Telegraph (Salt Lake City, UT), pg. 3, col. 7:
egislation, it is safe to say, never did and never will “vote up or down” the evils which Mrs. Stanton mentions.
 
30 November 1870, Albany (NY) Evening Journal, pg. 2, col. 2:
Now with reference to this Simon, Mr. White might possibly be pardoned for not knowing whether he says “thumbs up” or “thumbs down” on the tariff question.
 
16 March 1871, Democratic Expounder and Calhoun County Patriot (Marshall, Calhoun County. MI), pg. 2, col. 2:
It may thus be set down as doubtful if the electors will soon have an opportunity to vote up or down any proposition looking toward the increase of the salaries of any public or State official.
 
3 October 1873, Hartford (CT) Courant:
The state will pay the amount appropriated any way, whether the amendment is voted up or down.
 
18 September 1913, Oregonian (Portland, OR), pg. 10, col. 4:
VOTING PROHIBITION UP OR DOWN.
   
26 April 1932, Springfield (MA) Daily Republican, “Omnibus measure to be rushed by House tomorrow,” pg. 3, col. 4:
The Indianan declared that procedure that would force “an up or down vote” should be invoked, adding, “that’s the only thing that will satisfy the people of the United States.”
     
30 March 1941, Abilene (TX) Reporter-News, pg. 14, col. 1:
Any recommendations the charter commission may make will have to be voted on by the people in an election which can’t be held until a year from next December—plenty of time to make up our minds whether to vote them up or down.

4 April 1946, Gastonia (NC) Daily Gazette, “Senate Expected to OK Compromise Base Of 60 Cents For Mimimum Pay,” pg. 1:
“There is going to be a clear-cut, up or down vote on my amendment before final action is taken on this bill,” he told a reporter.
 
New York (NY) Times   
Up-or-Down
By WILLIAM SAFIRE
Published: August 14, 2005
(...)
That means an up-or-down vote on substance is roughly synonymous with a recorded yea-or-nay vote, a roll-call vote and — also in informal usage — a clean vote. It is distinct from a vote on procedure, like a motion to table, to recommit, to amend an amendment or to end debate in a filibuster.